Struct VQE 

pub struct VQE<A: Ansatz> { /* private fields */ }

Variational Quantum Eigensolver for ground state energy estimation.

Example

use logosq_algorithms::{VQE, Hamiltonian, HardwareEfficientAnsatz};

let hamiltonian = Hamiltonian::new(4);
let ansatz = HardwareEfficientAnsatz::new(4, 2);
let vqe = VQE::new(hamiltonian, ansatz);
println!("VQE has {} parameters", vqe.num_parameters());

Implementations

impl<A: Ansatz> VQE<A>

pub fn new(hamiltonian: Hamiltonian, ansatz: A) -> Self

Create a new VQE instance.

pub fn with_shots(self, shots: u32) -> Self

Set the number of measurement shots.

pub fn with_max_iterations(self, max_iterations: usize) -> Self

Set the maximum iterations.

pub fn with_convergence_threshold(self, threshold: f64) -> Self

Set the convergence threshold.

pub fn with_optimizer(self, optimizer: &str) -> Self

Set the optimizer.

pub fn num_parameters(&self) -> usize

Get the number of variational parameters.

pub fn evaluate(&self, parameters: &[f64]) -> Result<f64, AlgorithmError>

Evaluate energy for given parameters.

pub fn evaluate_with_gradients( &self, parameters: &[f64], ) -> Result<(f64, Vec<f64>), AlgorithmError>

Evaluate energy and gradients using parameter-shift rule.

pub fn run(&self) -> Result<VQEResult, AlgorithmError>

Run the VQE optimization.